Self-reflection is a central goal of personal informatics systems, and constructing visualizations from physical tokens has been found to help people reflect on data. However, so far, constructive physicalization has only been studied in lab environments with provided datasets. Our qualitative study investigates the construction of personal physicalizations in people's domestic environments over 2-4 weeks. It contributes an understanding of (1) the process of creating personal physicalizations, (2) the types of personal insights facilitated, (3) the integration of self-reflection in the physicalization process, and (4) its benefits and challenges for self-reflection. We found that in constructive personal physicalization, data collection, construction and self-reflections are deeply intertwined. This extends previous models of visualization creation and data-driven self-reflection. We outline how benefits such as reflection through manual construction, personalization, and presence in everyday life can be transferred to a wider set of digital and physical systems.

Evaluation is increasingly recognized as an essential component of HCI research. However, evaluation itself is a changing research area. In particular, the many variations of qualitative research are emerging as important empirical methods. This half-day tutorial is designed for beginning to intermediate audiences. We will focus on the basic methods for analyzing qualitative data using a mixture of talks and hands-on activities. In particular we will consider closed and open coding as well as clustering and categorizing coded data. After completing this tutorial, attendees will have a richer understanding of the benefits and challenges of qualitative empirical research and, more specifically, how to analyze qualitative data.

We explore the presentation technique of visual abstraction as a form of mediation to manage content generated by the public in order to maintain a respectful discourse. We identify technological and social mediation as two dimensions within the space of content mediation, and discuss different solutions based on related work in public interactive displays and art installations. We further discuss a novel approach to technological mediation by describing our interactive artwork Objective Meaning - an installation that invites the audience to express themselves through anonymous text messages. The design of this system mediates discourse by visually abstracting the presentation of messages on a display by breaking messages apart into decontextualized words. We briefly discuss the public response during a one-month deployment of the installation in a library setting.

Stacked graphs are a visualization technique popular in casual scenarios for representing multiple time-series. Variations of stacked graphs have been focused on reducing the distortion of individual streams because foundational perceptual studies suggest that variably curved slopes may make it difficult to accurately read and compare values. We contribute to this discussion by formally comparing the relative readability of basic stacked area charts, ThemeRivers, streamgraphs and our own interactive technique for straightening baselines of individual streams in a ThemeRiver. We used both real-world and randomly generated datasets and covered tasks at the elementary, intermediate and overall information levels. Results indicate that the decreased distortion of the newer techniques does appear to improve their readability, with streamgraphs performing best for value comparison tasks. We also found that when a variety of tasks is expected to be performed, using the interactive version of the themeriver leads to more correctness at the cost of being slower for value comparison tasks.

In this paper we discuss the creation of visual mementos as a new application area for visualization. We define visual mementos as visualizations of personally relevant data for the purpose of reminiscing, and sharing of life experiences. Today more people collect digital information about their life than ever before. The shift from physical to digital archives poses new challenges and opportunities for self-reflection and self-representation. Drawing on research on autobiographical memory and on the role of artifacts in reminiscing, we identified design challenges for visual mementos: mapping data to evoke familiarity, expressing subjectivity, and obscuring sensitive details for sharing. Visual mementos can make use of the known strengths of visualization in revealing patterns to show the familiar instead of the unexpected, and extend representational mappings beyond the objective to include the more subjective. To understand whether people's subjective views on their past can be reflected in a visual representation, we developed, deployed and studied a technology probe that exemplifies our concept of visual mementos. Our results show how reminiscing has been supported and reveal promising new directions for self-reflection and sharing through visual mementos of personal experiences.

When searching through collections of books or written texts, the efficient yet limiting query paradigm is still the most dominant entry point. Previous work characterizes search processes in various contexts and describes them as integral and closely related to creative endeavours. We revisit this work from a design perspective, proposing guidelines for versatile search interfaces that are based on a modular approach to search. Inspired by aspects of search in physical environments, our recommendations address learning, creativity, inspiration, and pleasure as positive aspects of (book) search. Based on in-depth interviews with library patrons about search practises in physical and digital environments and drawing from previous work on search behaviour, we discuss search patterns as modular constructs consisting of micro-strategies. We illustrate how the structure of these patterns is highly flexible. Much like creative processes, they fluidly evolve based on learning and ideation during search, particularly in physical environments. This modular perspective provides a basis for designing interfaces that facilitate creative approaches to search in digital environments.

If visualization is to be democratized, we need to provide means for non-experts to create visualizations that allow them to engage directly with datasets. We present constructive visualization a new paradigm for the simple creation of flexible, dynamic visualizations. Constructive visualization is simple-in that the skills required to build and manipulate the visualizations are akin to kindergarten play; it is expressive in that one can build within the constraints of the chosen environment, and it also supports dynamics -- in that these constructed visualizations can be rebuilt and adjusted. We de- scribe the conceptual components and processes underlying constructive visualization, and present real-world examples to illustrate the utility of this approach. The constructive visualization approach builds on our inherent understanding and experience with physical building blocks, offering a model that enables non-experts to create entirely novel visualizations, and to engage with datasets in a manner that would not have otherwise been possible.

Serendipity, a trigger of exciting yet unexpected discoveries, is an important but comparatively neglected factor in information seeking, research, and ideation. We suggest that serendipity can be facilitated through visualization. To explore this, we introduce the Bohemian Bookshelf, which aims to support serendipitous discoveries in the context of digital book collections. The Bohemian Bookshelf consists of five interlinked visualizations each offering a unique overview of the collection. It aims at encouraging serendipity by (1) offering multiple visual access points to the collection, (2) highlighting adjacencies between books, (3) providing flexible visual pathways for exploring the collection, (4) enticing curiosity through abstract, metaphorical, and visually distinct representations of books, and (5) enabling a playful approach to information exploration. A deployment at a library revealed that visitors embraced this approach of utilizing visualization to support open-ended explorations and serendipitous discoveries. This encourages future explorations into promoting serendipity through information visualization.